I was wondering something. When I brew beer, I mash my grain for an hour or so at 60-70oC. I then separate the wort from the grain. Then I add hop into the boiling wort for 90 minutes.
My friend told me that he is doing his hopping boil for with the grain still in the mashtun. I mean after the mashing part, instead of separating the grain and the wort, he leaves the grains in the mashtun. He then proceed to add hops in this boiling mixture of wort and grain.
Is that bad or people do this ?